Optical inspection apparatus



May 16, 1933. K. K. LEDIG OPTICAL INSPECTION APPARATUS Filed Dec. 18, 1930 ATTORNEY Patented May '16, 1933 1,908,990

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Application fled December 18, 1980. Serial No. 508,141.

This invention relates to optical inspection apparatus is shown to comprise vertical supapparatus and more particular] to improveports 6 for a table 19 upon which is mounted ments in such apparatus in whic an image of V abracket 13 for holding the object being inthe article being inspected is projected upo spected and supporting an inclined mirror 14. a screen. a f Sup orted by the members 6 at the other Heretofore, in apparatus of this type im- 'slde o the table is a balopticon 10 of a well ages have been projected upon screens 'posiknown type including a lamp, which throws tioned at about ten feet from the operator, or 'a light upon an inclined mirror and lens arin some cases the screen has been positioned rangement 11 which projects the light a to the side of the operator. Inasmuch as the 7 hro gh a tube 12 to the object 15 supported object being inspected is usually not more y the bracket 13. I than twenty-five centimeters from the e e. As w1ll be seen in Figure 3 the path of the of the o erator, the constant changing of t e hg l avlng the balopticon is designated focus 0 the eye of the operator from the obby the dotted line a. The light iS diverted by ject to its image on a screen, causes great fathe inclined mirror 11 and then follows the tigue, resulting in inefiicient inspection, at P th as Shown by'dotted line b, which passes the same time materially retardingthe speed r ugh 01 around the object being inof inspection. spected until. it 7 caches the inclined mirror Wh n the s r en is o ition d along ide of 14 from whenceit is diverted to follow the the operator, similar atiguing efi'ects obtain, P h Shown by the dotted hne 0.

since the operator must continually shift his T proj cted image of the object 15 which h ad f m a d wn iti t n u and id is now following the path 0 strikes the mirror po iti n, 18 from which it is reflected along the path It is an object of this invention to provide don a screen 16 which is provided with vaan optical inspection apparatus in which the 110118 markings r projection screen is positioned at approxi- The Screen 16 1S mmed ately above the mately the same distance from the eye of an" m rr r l4 and the objectbemg 1nspected 15, operator as the object being inspected. and the rays 0 and d are in the same vertical A further object is the provision of an in- P a spection apparatus in which the projection T The m 13 1S Q h far extremlty'of the screen is positioned in line with and immedilarge tube 7 Whlch I m n d upon the supately above the object being inspected. ports 6, 8 and 9; the support 9be1ng verti- A further object is the provision of an'inl y w hl by me ns of a Screw and nut spection apparatus in which the parts are ng nt m lcated at 10.

35 so arranged as t ui a i i amount Thls apparatus is designed especially for of spac nd f ilit t bli d dnspectionof very small articles and the rojustment, ectlons upon the screen 16 indicate ily,

These and other advantageous bjeets by the marking 17, any deviations from' the which will later appear, are accomplished by p lfi d Size n Shape of the article being 40 the simple and practical construction and ari spe F or e p in the manufacture 9o rangement of parts hereinafter described and 0f spinerets, such as used in the production of exhibited in the accompanying drawing, rayon fibres, the apertures in the I spinerets f i t h f, d i hi h v are very small, approximately .003 inch in Figure-1 represents a side elevational view'- di m r, an mu be as round as possible in of the inspection apparatus. a order that the fibres may be perfect in shape.

Figure 2 represents a partial front eleva-. vImperfections in the shape of the apertures tional view of the apparatus. in the spinerets will cause grooves and ir- Figure 3 re resents a sectional side elevareflgular shaped fibres whichhave a marked tlonal view 0 elements in the apparatus. e ect in cloth made therefrom. Conse- Referrlng to the drawing, the inspection quently, the apertures are made with drills 10o which are as near as possible circular in cross section, and by means of the inspection a paratus'herein disclosed any deviation 0 the drills from the circular outline may be readily noted so that they may be corrected. Imperfectly shaped apertures in spinerets may also be readily discovered.

The apparatus also is applicable to the inspection of filaments as used in incandescent lamps and other electrical apparatus in order to discover any deviation from standard sizesv and shapes, and for the inspection of diamond, drawing or other dies, for the inspectifin of small drills, taps, punches and the li e.

Inasmuch as articles being inspected are exceedingly small, it is obvious that any means w ich will lessen the fatigue to the. operator, will also increase the efiicienoy of the inspection. Also photographs may be made of the image on the screen for permanent records. a

It will be readily seen that the screen 16 and the object 15 are at approximately the same distance from the eye of the operator, and consequently, it is not necessary for t e operator to continually adjust the focus of his eyes in order to see the object and then its image on the screen.

As a result, the inspection operation isnot fatiguing and the operator is enabled to more rapidly and efiiciently perform his task. Also since the screen and object beingv inspected are substantially in alignment, the operator does not have to move his head continually, it only being necessary to slightly shift the eyes in order to see either the projected image or the object.

By providing a long tube, the apparatus may be used in broad daylight in any room, and'a special dark room is not necessary, it being sufiicient' to shield the screen and the ob'eot from extraneous light.

11 order to protect the tube and other parts from the heat of the balopticon, an aluminum shield 20 is provided.

The foregoing disclosure is to be regarded as descriptive and illustrative only, and not as restrictive or limitative of the invention, of which obviously an embodiment may be constructed including many modifications without departing from the general scope herein indicated and denoted in the appended claim.

Having thus What I claim as new and desire to secure by Letters Patent, is:

In an apparatus of the class described, a projector including a lamp, a lens for receiving a beam of light from the projector, means for supporting an object to be tested in the focal plane of said lens between said lens and projector, a screen positioned directly above the object and in the same vertical. plane therewith, a tube having one end addescribed my invention,

'acent the screen and object, a mirror mounted 1n the opposite end of the tube for receiving the image projected through the lens and to reflect said image on to the screen, said tube being positioned above the lamp in the projector, and a shield positioned directly above the lamp and below the tube to rotect the tube from heat-generated by the amp.

KURT K. LEDIG. 

